ServiceNow: Robust Transform Engine Error UNderstnading

Hello team,

We are using Excel SGC from Operational Technology Module to load CI in CMDB. Upon transformation, for one of the related tables, its saying Insert Incomplete. I am not able to understand what mechanism of ETL/Robust Transformer writes this message. 

I want to understand more about error logging and how it works.

Thanks in advance,

Rahul